Roadway working apparatus



M. l. HUDIS ETAL ROADWAY WORKING APPARATUS March 7, 1961 9 Sheets-Sheet1 Filed March 25, 1955 INVENTORS` M ICHHL 1. H0015 /lullllllll Bf, JaccoJ. mancano N .ma

March 7, 1961 M. HuDls ETAL RoADwAY WORKING APPARATUS Filed March 25,1955 9 Sheets-Sheet 2 INVENTORS Murmel. :.Huozs Bt J'Hco J. Manna wwwMarch 7, 1961 M. l. HUDls ETAL 2,973,723

ROADWAY WORKING APPARATUS March 7, 1961 Filed March 25, 1955 M. l. HUDISET AL ROADWAY WORKING APPARATUS 9 Sheets-Sheet 4 d gg N x v0 U a JI l w2 P |l un I| j V sa l il* I |I ,11T-:Iii Ill, l l 3 Iil 1 :k l

l. i l@ f N mmfvwfzs 1" Bf, Jncoa Macau-a March 7, 1961 M, l, HuDls ETAL'2,973,723

ROADWAY WORKING -APPARATUS March 7, 1961 M. l. HuDls Erm. 2,973,723

ROADWAY WORKING APPARATUS Filed March 25, 1955 9 Sheets-Sheet 6INVENToRs MNHN I. H0015 BY .18:03 J. MRRctLLo March 7, 1961 M. l. HuDlsETAL 2,973,723

Y ROADWAY WORKING APPARATUS Filed March 25, 1955 9 Sheets-Sheet 7INVENTORS MICHRIL :.Hurs BY JRcoB J. MHRCBLLo ttorney March 7, 1961 M.Hunls Erm. 2,973,723

ROADWAY WORKING APPARATUS Filednarch 25. 1955 9 sheets-sneet s INVENTORSMICHIIL I. H0013 BY JHCQB J. MRRCELLQ MMM March 7, 1961 M, HUDIS ETAL2,973,723

ROADWAY WORKING APRARTUS Filed March 25. 1955 l9 Sheets-Sheet 9INVENToRs MICHREL i., Hunts MJMQW United States Patent ,i

ROADWAY WORKING APPARATUS Michael I. Hudis and Jacob J. Marcello,Warren, Ohio;

Filed Mal'. 25, 1955, Ser. No. 496,851

2 Claims. (CI. 10S-178) The present invention relates to apparatusadapted to travel along longitudinally extending, transverselyspacedapart supporting surfaces which may incline vtoward or away fromeach other, more particularly to roadway working apparatus adapted totravel along the usual road forms which normally deiine the edges of theintended roadway and which, in certain cases, may be disposed inconverging orA diverging relationship, and the principal object of theinvention is to provide new and improved apparatus of such character.

Modern highway construction, particularly so-called super-highwayconstruction, dictates the use of gently curving entrance and exit roadswhich intersect the main road at a tangent to minimize traiiic 4iiowdisturbances at these points. Road constructions of this type often varyin width, changing from wide to narrow and vice versa in accordance withintersection requirements, bridges, curves, grades and the like. Thesewidth changes generally progress gradually from one to the other and tomeet these requirements, the finishing machines and other alliedapparatuses which normally ride the forms defining the edges of theintended roadway must be capable of expanding and contracting in widthto maintain the road form engaging wheels of the apparatus upon the roadforms despite divergence of convergenceof the latter. Y

l In the past, apparatus has been devised wherein roadV form engagingiianged wheels float axially toward and away from each other toaccommodate converging ory diverging road forms. In most instances, thewheels on one side of the apparatus which are engageable with onel roadform are maintained in axially iixed relation relative to the main bodyof the apparatus while the wheels on the other side, engageable withtheother road form, are lallowed to float axially.

This construction has not been satisfactory since the one road formalone must guide the apparatus along the forms and resist all of theforces tending to shift the apparatus transversely thereof. Furthermore,-with prior art constructions, the weight of the apparatus is seldom, ifever, evenly divided between the two forms. This causes considerablediiculty in operating kthe apparatus since the uneven loading conditionoften causes one side of the apparatus to advance down the forms at agreaterv ing'description and from the drawings appended hereto.`

v being removed in the interest of clarity,

Patented Mar. .7, .1961

ice

Figure 1 is a top plan view of apparatus illustrating anv v embodimentof the present invention,

Figure 2 is an enlarged side elevational view of the apparatus shown inFigure 1,

Figure 3 is an enlarged sectional view generally corresponding to theline 3-3 of Figure l,

Figure 4 is a fragmentary, enlarged front elevational view'of theapparatus shown in Figure l, certain parts being broken away toillustrate interior construction,

Figure 5 is a view similar to Figure 4 but with certain parts furtherbroken away and removed to better illusf` trate the interiorconstruction,

Figures 6 and 7 are transverse fragmentary sectional views generallycorresponding to respective lines 6-6 and 7-7 of Figure 5,

Fig'ure 8 is a broken perspective view of the main frame of the hereindisclosed apparatus, certain parts' normally secured thereto beingremoved in the interest of clarity, Figure 9 is a broken perspective,view of one of two frame extensions forming a part of the presentlydis" closed apparatus, certain parts normally secured thereto;-

Figures 10 and llfare reduced size, top plan views of the frame of theapparatus, all parts normally carried thereby being removed in theinterest of clarity and thel views respectively showing the frame incontracted and expanded relation,

" lIn thel drawings accompanying this specilication` and f Y Figure 12is a generally diagrammatic view of a' iiuid circuit for-operating theembodiment of the invention shown in Figures 1 through 11,

Figure 13 is a fragmentary sectional view *generally I corresponding tothe line 13-13 of Figure 3 but of a modiiied construction, and

Figure 14 is a generally diagrammatic view of a tiuid circuit foroperating the embodiment shown in Figure 13;

The present invention is shown applied to a road iinishing machineadapted to span the road forms which deline the edges of the intendedroad and having a plurality of spaced-apart wheels which engagelrespective forms; Such a machine normally carries a screed which "isadapted to be reciprocated'transversely ofthe roadway as the iinishingmachine progresses along the forms toV smooth the plastic roadmaterialand form its upper surface to the desired contour, `be it iiat,curved, or other wiseproiiled. It is to be understood, however, that theapparatus herein disclosed is illustrative only and that the inventioncan also -be Iapplied to other apparatus such as spreading, spraying,floating and joint installing apparatus commonly employed in highwayconstruction.

Referring to Figure 1, it will be noted that the presentembodimentcomprises a frame structure 10 rotatably carrying a pair of wheels 11 oneach side. The wheels on each side are adapted to be supported lby theusual road forms 12 which normally dene the sides of the intendedroadway, the wheels 11 being of the doublev flanged type to reduce thepossibility of Ithe apparatus running off the forms and the Aspacingbetweenthe flanges being somewhat 'greater than the width of' the upperportion of the forms upon which the wheels ridev (see Figure 5) for apurpose to become clear.A

As best shown in Figures 1,12, 3 and 4, frame structure 10 carries ascreed 13 which extends transversely ofthe intended roadway and which,in normal use, rests upon the tops of the forms 12 in the mannerAillustrated. By means later to be disclosed, screed 13r is adapted to bereciprocated transversely of the roadway as the appa# ratus,l movesalong .the forms on the wheels 111. .f

While the embodiment herein disclosed employs but a single screeddisposed at the front of the machine, it is to be understood thatanother screed, similar to the one herein shown, may be disposed at the.rear of the machine -if desired.

' Means are provided for elevating the screed 13 when the apparatus isto be transported or when the use of the screed is not required. As seenin Figures 1 through 4, a shaft 14 is supportedV by suitable bearings 15secured to members 16 which extend transversely of the frame structurein overhanging relation with the screed and which are secured to the topof such structure by` welding or the like. Adjacent each end of shaft14, a chain 17 is secured, and each chain extends downwardly toward thescreed and each terminates in a link 18 which rotatably carries a roller19 (see Figure 3). Secured in spaced relation to the top of the screedadjacent each chain 17 by means of brackets 20 is a bar, or track, 21adapted for engagement with roller 19.

When shaft 14 is rotated in a clockwise direction (with reference to thearrangement of parts as shown in Figures 2 and 3) by means of a uidcylinder 22 connected to a lever 23 suitably secured to the shaft 14,each chain 17 will be wrapped about the shaft 14 thus pulling up on therespective links 18 which carry rollers 19. As rollers 19 are elevated,they will engage beneath respective bars 21 and thus raise the screed.Since suicient space is provided between the respective brackets 20which support each bar 21, the screed may be raised, if desired, withoutinterrupting `its reciprocatory movement. While only two chains 17 areherein disclosed, it will be understood that additional chains may beemployed if required.

With particular reference to Figure 3, but as also shown in Figure 5,means are provided for pushing the screed ahead of the apparatus againstthe resistance of the road material which piles up in front of thescreed as the apparatus moves in a forward direction along the forms. Inthe herein disclosed embodiment, a pair of push rods 24 extend from theouter members 16 to the screed. One end of each push rod 24 ispivotally-secured to the screed by means of respective brackets 2S andthe other end of each push rod is pivotally secured to respectivemembers 16 by means of respective brackets 26. It -is to be understoodthat the pivotal connections of the push rods 24 with the screed and the`members 16 will have suflicient play, or slack, so

, 4 of the apparatus are connected together for unitary rotation bymeans of a suitable chain 38 operating over sprockets 39 carried byrespective wheels.

As most clearly shown in Figures 2, 3 and 4, a shaft 40 extends forwardfrom the drive mechanism 28 and terminates lin a sprocket 41. A sprocket42 is rotatably carried by the frame structure directly beneath sprocket41 and a suitable chain 43 connects `the two sprockets together. A stud44 is secured to, by any suitable means, and projects forwardly from theside of sprocket 42 in off-set relation with the rotational axis of thelatter. Stud 44 serves as a crank arm to which one end of a link 45 isrotatably secured. The other end of link 45 is pivotally secured to astud 46 (see Figure 4) carried by screed 13. It will readily be apparentthat as sprocket 42 is rotatedby means of shaft 40, the off-set positionof stud 44 will effect reciprocation of link 45 and y consequentreciprocation of screed 13.

l upper surface of the channel members 47a by means that the push rodsdo not interfere with elevation of the screed iu the manner heretoforedisclosed.

As seen in Figures l through 5, frame structure 10` is provided with aplatform 27 which supports the drive mechanism 28 of the apparatus. Thedrive mechanism may take any convenient form; however, the drivemechanism preferred at the present time is a gasoline engine 29 which isoperably connected to a suitable gear box 30. Although not shown,suitable clutches may be employed to provide for selective interruptionof power transmission lfrom the drive mechanism., Extending from gearbox 30 `toward the wheels at respective sides of the apparatus is adrive shaft 31. Each side of the drive shaft 31 is rotatably supportedby a bearing 32 secured to respective members 116 and each drive shaftis preferably hollow for a purpose to appear. vPositioned withinrespective ends of the hollow drive shaft 31 are shaft extensions 33which are keyed to the shaft for unitary rotation therewith butwhich areslideable axially thereof. Each shaft extension 33 is rotatably carriedfby a bearing 34 secured to a portion of the frame structure 10.

l As best shown in Figures l, 2 and 5, a sprocket 35 is carried by eachshaftextension 33 and each sprocket of suitable spacers, or pads, for apurpose to become clear.

Secured to the respective inner sides of the channel members 47a, inback to back relation therewith and disposed at one end thereof, are apair of channel members 47b. Channel members 47b are securely Vwelded tomembers 47a as indicated and plates 50 are welded in place between thelegs of respective members 47b to provide a at smooth surface for apurpose to be disclosed.

The previously mentioned frame extensions 48 and 49 are adapted to becarried by the main frame 47 in telesooping relation to provide foradjustment of the size of the apparatus. As seen in Figure 9, frameextension 48 comprises a pair of spaced channel members 48a securedtogether as by welding or the like by a pair of spaced cross members 48hdisposed at one end. In a manner similar to that employed with members47b, plates 51 are welded between the legs of channel members 48a for apurpose to be disclosed. v

, Frame extension 49 is similar to frame extension 48 with the exceptionthat while the overall width of extension 49 is such that it slideablyfits between members 47a of the main frame, the overall width ofextension 48 is such that it slideably ts between the members 47b of theframe extensions, drive shaft length will increase and isA connected bymeans of. a drive chain 36 to a sprocket l 37 carried by a respectiveadjacent wheel 1'1. In the present embodiment, the wheels 1-1 onrespective sides decrease `automatically as the frame extensions aremoved relative to the main frame thus maintaining constant alignmentbetween the associated drive sprockets and chains.

Means are provided for maintaining the relatively movable frame portionsin alignment without impeding such movement and, as shown in Figure l, aplurality of rollers are carried by the main frame for engagement withrespective frame extensions. Since a similar arrangement 1s employed toguide each of the frame extensions, only the ones employed withextension 48 will be shown and described indetail."

Secured to'the top of main frame 47 by suitablebrackets are a pair offspaced-apart rollers 52 (Figures 1 and 4) which are engageable with ytheupper surface of frame extension 48. Corresponding rollers 52 arecarricdby each of the spaced members which comprise the main frame and eachroller 'is engageable with a respective member 48a of the frameextension 48 (see Figure 2). Furthermore, as most clearly seen inFigures 5 and 7, the rollers 52 at the top of the frame are matched bysimilar rollers 52 positionedfor engagement with the underside of theframe extension.

In addition to rollers 52, spaced'rollers53 are carried by brackets` 54secured to the main frame, rollers 53 being engageable with respectiveplates 5I as shown in Figure 6 for the purpose of holding the respectiveframe extension members closely against the respective inner surfaces ofthe main frame.

Means are provided. for shifting. the frame extensions and therespective wheels carried thereby transversely of the road'form's V12 soasV to maintain theA Wheels upon the forms despite convergence ordivergence of the latter. In the presently disclosed embodiment,positive, power operated means are employed to effect shifting ofrespective frame extensions relative to the main frame and as seen inFigure l, iluid cylinders 55, 56 are employed for this purpose.

As most clearly shown in Figure 5, cylinder 55 has one end, in thisinstance its blank end, secured to the under# side of the platform 27 bymeans of a bracket 57. Piston rod 58 of'cylinder 55 is in turn securedto one of the members 48b of frame extension 48` by means ofa bracket59. Since cylinder 56 -is mounted in manner similar to cylinder 55 (withthe exception, of course, that it is connected to frame extension 49),it is not believed that a detailed description thereof is necessary.

In Figure l2 there is generally diagramrnatically shown a hydrauliccircuit for controlling oper-ation of the cylinders 55, 56, The circuitcomprises a fluid pump, two

manually operable Huid' control valves 60; 70 having re-k spectiveactuators 60a, 70a, fluid cylinders 55, 56 and associated connectingconduits. Valves 60, 70 are herein shown to` be identical and, althoughnotrshown, each is preferably spring-biased toinsure its return to theneutral position illustrated when the actuator isV released. It is to13e-understood that thesevalves will be positioned on the machinewithineasy reach ofthe operator who normally rides upon the platforml27. Valve 60 hasv ports 62, 63, 64, 65 66, 67 and 68 While valve 70 hasports 72, 73, 74, 75,76, 77-and 78.

Ports 62, 64v of valve 60 and port 74 of valve 70 are connected with thepressure ,outlet side of the pump by means of conduits 80 while ports`72, 73 and 75 of valve 70 are connected with the return inlet of' thepump by' means of conduits 81. A conduit 82 connects -port 68',

with port 78 and condui-ts 83, 84 respectively connect ports 66, 67 withthe rod and blank ends of cylinder 55; Conduite 85, 86 respectivelyconnect ports 76, 77 with f the rod andl blank ends oficyli'nder 56.

With valves 60, 70, in the neutral position shown and With the pump(which may be ,driven by thedrive mechanism ofthe apparatus) operating,ilu idwill pass, through conduit 80 tol port -62,"through valve 60and'out port 68 to valve 70 throughconduit 82 and port 78. The fluidwil-l,

, the respectivev valves 60, 70. This insures that the cylinders kwillremainina fixed position, thus-holding the wheels 11 in 'predeterminedspaced-apart relationt'as long as the valves are in neutral.

During operation of the apparatus along the road forms, the operatorriding thereon, upon observing that the road forms are converging ordiverging, will actuate the valves 60,` 7 0 tov extend or contract theframe extension members to thereupon maintain the road form engagingwheels in engagement with the forms. Normally, both valves will beactuated simultaneously to shift the frame extensions in oppositedirections, either toward or away from each other. However, if desired,the valves m-ay be operated to shift cylinders 55, 56 (and consequentlythe frame extension members) in the same direction to thereby merelyVshift the mainframe of the apparatus toward one or the other road formswithout changing the spacing between the wheels. Moreover, if desired,only one valve may be actuated to thereby effect shifting of only one ofthe frame extensions. In Order to simplify understanding of the uidappara; tus shown in Figure 12, operation thereof when only valveV 60 isactuated will first be described. YAssuming that the operator shifts theactuator 60a of valve 60 from the full line position shown. to dottedline position X, the spool Within the valve will be shifted to close oithe previously described. free ilowing, or by-pass, circuit throughports 62, 68 and to establish communication between ports 64 and 66 andbetween ports 63 and 67.

vWith. the by-pass circuit interrupted, lfluid will How from the pumpthrough the valve and to the rod end of cylinder 55' through `conduit80ports 64, 66 and con;y duit 83., Fluid will be displaced from theblank end of cylinder 55 through the valve` and to the inlet of the pumpthrough conduit 84, ports 67, 63 and conduit 81. Accordingly, thepiston. rod of cylinder 55 will be retracted. When the operator releasesactuator 60a, it will be returned .by any suitable means (not shown) toits full' line position to lockcylinder 55 in position and re-establishthe by-pass circuit. C Moving actuator 60a to position Y will 'onceagainv interrupt the by-pass circuit and establish communication*ybetween ports 65, 66 and between ports 64, 67. Fluid' will now tlow fromthe pump through the valve to the blank cndof cylinder 55 throughconduit 80, ports 64,' 67, and conduit 84. Fluid will be displaced fromthe rod end of Vcylinder55 through the valve and to the inlet of thepump through` conduit 83, ports 66, 65,' and con-- duit 81. Accordingly,the piston rod of cylinder 55 wilt be extended', j With the foregoingdescription of operation of va'lve 60, it is believed that a detaileddescription of operation of valve 70 is unnecessary since the operationof this valve will'nowbe evident. Note that in the event either valveactuator is shifted from its full line position, the

Figure -14 isl a modified hydraulic circuit design which willautomatically shift the road form engaging wheelsV of the apparatustoward or away from each other in response to convergence or divergenceof the road" forms without constant attention from the operator. tBriey,this circuit comprises a pair of valves 160, 170which are somewhatsimilar to valves 60, 70; a fluid pump; a spring-centered, pilotoperated valve ;*a manually `operable valve 91 having an actuator 91awhich is normally held in the neutral position illustrated by suitablesprings (not shown) or Ithe like; uid cylinders 155, 156 which. aresimilar toV cylinders 55, 56; andr a plurality of conduits which connectthe various members of the circuit together. i

Valves 160, are not adapted for manual operation as were valves`60, 70;instead, each. has its actuator en# gageable'with a'respective road formby means of the. following mechanism; .i In.A the modiiiedcoustruutimtshown in Figure 13, the main body of valve 160 is secured toframe extension 48 by bolts or the like. Also secured to frame extension48 are a pair of spaced lugs 92 (only one of which is shown) whichsupport a pivot shaft 93. Pivotally carried by shaft 93 between the lugs92 is a yoke 94 which rotatably carries a feeler wheel 95 engageablewith the road form 12 on this side of the machine. Feeler wheel 95 ispreferably positioned be- 4tween the wheels 11 on this side of themachine and this wheel is formed with spaced ange portions to insureengagement with the road form. Secured to and extend ing upwardly fromyoke 94 is an arm 96 which is pivotally secured to the actuator 160a ofvalve 160.

, From the construction illustrated in Figure 13, it will be understoodthat in the event relative movement occurs in a direction transverselyof the road forms between the latter and the finishing machine (suchrelative movement occurring because of transverse shifting of themachine or because of a non-parallel relationship between the roadforms) feeler wheel 95 will be tilted in one direction or the otherabout its pivot shaft 93 thus effecting movement of valve actuator 160a.Although not shown, valve 170 is arranged in a manner similar to valve160, valve 170, of course,` being carried by frame extension 49 andhaving its feeler wheel engaged with the opposite road form 12.

It should be pointed out that in the operation of road machines of thegeneral type herein disclosed, considerable power must be applied to thescreed to elect transverse shifting thereof. This is particularly truewhen relatively large amounts of road material pile up in front of thescreed. Accordingly, it is not at all unusual for the machine tooscillate transversely of the road forms as it progresses therealong. Inview of the fact that such movement frequently occurs, the circuitdisclosed in Figure 14 has been designed to effect operation of thecylinders 155, 156 only when the feeler wheels move in oppositedirections thus indicating that the forms are in diverging or convergingrelation. In the event the machine shifts transversely of the forms (forreasons hereinabove disclosed), the feeler wheels will move in the samedirection and the cylinders will therefore remain locked in position tomaintain the form engaging wheels 11 in xed, spaced-apart relation.

Referring to Figure 14, valves `160, 170 are spool type valves, therespective spools of each being pivotally connected to their respectiveactuators and being shifted thereby. Valve 160 has ports 161, 162, 163,164, 165, 166, 167 and 168 while valve 170 has ports 171, 172, 173, 174,175, 176, 177 and 178. For a purpose to become clear, the spool, ofvalve 160 is formed with apertures 169 while the spool of valve I170 isformed with apertures 179.

I As previously mentioned, valve 90 is a pilot operated, spring-centeredvalve having a valve spool adapted to be shifted by pilot pistons 97 and98 respectively disposed at opposite ends of the valve. Valve 90 hasports 99, 100, 101, 102, 103, 104 and 105 connected to various conduitsyin a manner to be disclosed.

, Manually operable valve 91 has ports A106, 107, 108, 1 08a, 109, 110,111, 112, 113, 114, 115, 116, 117 and 118 and, as before disclosed, thespool of valve 91 is adapted to be resiliently held in the neutralposition shown by suitable springs or the like (not shown).

A conduit 119 connects the pressure outlet of the uid pump with ports106, 108 and 110 of valve 91 while a conduit 120 is connected to ports114, 115 of valve 91 and leads to a conduit 121. Conduit 121 hasbranches whichrespectively connect with ports 172 and 174 of valve-170and with ports 162 and 164 of valve 160. Conduit 121 further has abranch 122 which connects with port-101 of pilot valve 90.

' .A conduit 123 leads from the inlet of the fluid pump and connectswith a conduit 124 having branches connected to ports 171, 173 of valve170 and to ports 161,

163 of valve 160. Conduit 124 further has branches 125, 126 respectivelyconnected to ports .111, 118 of valve 91. Conduit 124 additionally has abranch -127 connected to port 175 of valve 170 and to port 99 of pilotvalve and a branch 128 connected to port 165 of valve 160 and to port103 of pilot valve 90.

A conduit 129 connects port 100 of pilot valve 90 with the blank end ofcylinder 155 and with port 109 of valve 91 while a conduit 130 connectsport 105 of the pilot valve with the blank end of cylinder 156 and withport 107 of valve 91. A conduit 131 connects port 102 .of the pilotvalve with the rod end of cylinder 156 and with ports 112, 113 of valve91 while a conduit 132 connects port 104 of the pilot valve with the rodend of cylinder 155 and with ports 116, 117 of valve 91. The chamber inwhich pilot piston 97 is slideable is connected to ports 166, 168 ofvalve 160 by means of a conduit 133 which has a branch 134 connected toport 178 of valve 170. The chamber in which pilot piston 98 is slideableis connected to ports 176, 177 of valve 170 by means of a conduit 135which has a branch 136 connected to port 167 of valve 160.

With all valves in the neutral position illustrated, it will be notedthat conduit 130, which is connected to the blank end of cylinder 156,terminates at closed port 107 of valve 91 and closed port 105 of thepilot valve 90 while conduit 131, connected to the rod end of cylinder156, terminates at closed ports 112, 113 of valve 91 and closed port 102of the pilot valve. Conduit 129, which is connected to the blank end ofcylinder 155, terminates at closed port 109 of valve 91 and closed portof the pilot valve while conduit 132, connected to the rod end ofcylinder 155, terminates at closed ports 116, 117 of valve 91 and closedport 104 of the pilot valve. Since fluid can neither enter nor escapefrom cylinders 155, 156 at this time, the cylinders are locked inposition to hold the wheels 11 in fixed, spaced-apart relation.

While the valves are in neutral, fluid will circulate idly through thepump, its llow being traced through conduit 119 to port 108 of valve 91,from port 108 to port and from port 115 to conduits 120 and 121. Fromconduit 121, a portion of the uid will ow to port 164 of valve 160,through apertures 169 in the valve spool, through port 165 and thence tothe inlet of the pump via branch conduit 128, and conduits 124, 123.Also from conduit 121, the remaining portion of the uid will ow to port174 of valve 170, through apertures 179 in the valve spool, through port175 and thence to the inlet of the pump via branch conduit 127 andconduits 124, 123. It will be noted that in the event only one of thevalves 160, 170 is shifted, fluid will continue t0 idle through the pumpthrough the valve which remains in neutral; accordingly, there will beno build up of pressure to cause shifting of the pilot valve 90 from itscentral, or neutral, position and, therefore, both cylinders 155, 156will remain locked in position.

In the event both valve actuators 160:1, 170a move in the same direction(caused by the previously described transverse shifting of the machine)and assuming, for example, that-actuator 160a moves to position Y andthat actuator 170a moves to position X, fluid flow through ports 164,174 of the respective valves will be cut olf. Fluid from the pump outletwill then ilow through ports 162, 167 of valve 160, through conduits136, to port 177 of valve 170. From port 177, uid will ow through port173 and to the inlet of the pump via conduits 124, 123. Since thiscircuit provides a free path for the fluid, once again no pressure willbe built up to effect shifting of the pilot valve. It is to beunderstood that a similar free path will be opened for the fluid in theevent valve actuator a moves to position X and valve actuator 170a movesto position Y.

When valve actuators 160a, 170:: move in opposite.

directions (caused by, for example, the road forms 12 actuator will beshifted to the respectivek positions `indicated at X or Y'. Movement ofvalve actuator'p160aY to position X (as by the fceler wheels 95 beingmoved away from Veach other by diverging road forms) will close offports 164 and 166 and establish communication between ports 163 and 167and between ports 162 and 168, while movement of valve actuator 170a toposition X will close off yports 174, 176 and establish communicationbetween ports 173 and 177 and between ports 172 and 178.

Fluid will then ow from conduit 121 through ports 162 and 168 of valve160 and to pilot valve piston V97 through conduit 133. Fluid will alsoilow topilot valve piston 97 through valve 170 through ports 172, 178and conduit 134. Fluid ahead of pilot piston 98 will be returned to theinlet of the pump through conduit 135, ports 177, 173 of valve 170 andthrough conduits 124, 123.` Fluid will also be returned to the inlet ofthe pump through conduit 136 (which connects with conduit 135), ports167, 163 of valve 160 and through conduits 124, 123. Since tluid fromthe pump will be admitted to pilot piston 97 and since uid ahead ofpilot piston 98 will be returned to the pump, the valve spool of thepilot valve will be shifted to the left.

When the valve spool of the pilot valve is shifted to the left,communication will be established between ports 102, 103 and 104, andbetween ports 100, 101 and 105. Fluid from the pump will then flow fromconduit 121 through branch conduit 122 to port 101 and thence throughports 100, 105. First considering iiuid ow through port 105, uid willpass to the blank end of cylinder 156 through conduit 130 (note thatport 107 of valve 91 is closed so that fluid in conduit 130 cannot passthrough the valve). Returning now to port 100 of the pilot valve, fluidwill ow through this port to the blank end of cylinder 155 throughconduit 129 (note that port 109 of valve 91 is closed at this time).

Returning to ports 102, 103 and 104 of the pilot valve and lirstconsidering port 102, uid from the rod end of cylinder 156 will flowthrough conduit 131 to ports 102, 103 and thence to the inlet of thepump through branch conduit 128 and conduits 124, 123. Fluid from therod end of cylinder 155 will flow through conduit 132, ports 104 and 103and thence to the inlet of the pump through branch conduit 128 andconduits 124, 123.

With the pressure outlet of the pump connected to the blank ends ofcylinders 155, 156 and with the rod ends of the cylinders connected tothe inlet of the pump, the piston rods of these cylinders will be forcedoutwardly thus moving the frame extensions 48, 49 and also the wheels 11away from each other to accommodate the diverging road forms. When theapparatus has been widened sufficiently, feeler wheels 95 will bereturned to their neutral position as will valves 160, 170 respectivelyactuated thereby. Accordingly, pilot valve 90 ,will be returned to itsneutral position shown by its springs thus locking cylinders 155, 156 inposition as before described.

It will be understood that when valve actuators 160a, 170a are shiftedto respective Y positions, as by the feeler wheels 95 being moved towardeach other by converging road forms, the pilot valve 90 will be shiftedin the opposite direction to that heretofore described thus admittingfluid to the rod ends of both cylinders 155, 156 and allowing uid Yfromthe blank ends of the cylinders to return to the inlet of the pump. Thiswill move the frame extensions 48, 49 and also the wheels 11 toward eachother to accommodate the converging road forms 12.

Since the present embodiment of the invention employs separate cylinders(155, 156) for shifting respective sides of the apparatus and sincethere is a possibility that the cylinders may not be shifted exactly thesame amount by reason of, for example, uneven loading of the apparatus,manually. operable valve 91 is provided to permit the operator to extendone of the frame extensions while simultaneously retracting the otherextension. Clearly, this will effect movement cf the main frame of theapparatus in `one direction or the other, depending,

upon which direction actuator 91a is shifted, without changing thespacing between the wheels 11.

It was previously pointed out that all fluid ow from the pump outlet tovalves 160, 170 passes through valve 91 via conduit 119, ports 108, 115and through conduit 120 to conduit 121. Accordingly, when valve actuator91a is shifted in either direction from the neutral position shown,ports 10S, 115 will be closed rand port 114 (connected to conduit 120 bya branch 137) will cornmunicate with port 108:1. Port 108a is connectedto the inlet of the pump by a conduit 138; therefore, any pressure whichmight exist in conduit i120 and the circuits connected therewith, byvirtue of the fact that extension or contraction of the machine istaking place at the time valve 91 is manually shifted, will `be bled offto the inlet of the pump and this will allow the pilot valve to returnVto neutral.

During operation of the finishing machine and assuming that the mainframe of the machine is closer to one road form 12 than it is to theother, the operator will shift the actuator 91a in the proper directionto center themain frame between the forms. By way of illustration andassuming that the actuator 91a is shifted to the right, ports 10S, 115will be closed andports 108a, 1l14 will be opened to each other asbefore mentioned. Ports 109, 113 and ports 110, 112 will be placed incommunication with each other as will ports 107, 116 and ports 117, 118.

Fluid will now ilow from the pump outlet through conduit 119 to port 110(ports 106 and 108 now being closed) and thence through ports 112, 113and 109. nFluidl iiow through port 12 will pass to the rod end ofVcylinder 156 through conduit 131 and to the blank end of cylinder 155through ports 113, 109 and conduit 129. Fluid from the bland end ofcylinder 156 will pass through conduit 130, ports 107, 116, through port117 via a portion of conduit 32, and through port 118 to conduits 126,124 and 123 to the pump inlet. Fluid from the rod end of cylinder 55will pass through conduit 132 to ports 117, 118 and through port 118 toconduits 126, l124 and 123 to the pump inlet.

With the rod end of cylinder 156 connected to the pump outlet and theblank end of this cylinder connected to the pump inlet, and with theblank end of cylinder 155 connected to the pump outlet and the rod endof this cylinder connected to the pump inlet, cylinder 156 and the frameextension connected thereto will be retracted and cylinder 155 and itsframe extension will be extended. Accordingly, the main frame of themachine will be shifted away from one road form and toward the otherwithout changing the spacing between the form engaging wheels 11. v

When the main frame is properly positioned between the road forms, theoperator will release `actuator 91a and the valve will then return tothe neutral position shown in the drawing. This will re-establishcommunication between the outlet of the pump and the valves 160, 170 andtherefore control of uid flow to and from cylinders 155, 156 will onceagain lbe placed under the control of valves 160, 170.

It will readily be apparent that shifting valve actuator 91a to the leftinstead of to the right will reverse flow of fluid and thus causeshifting of the main frame of the nishing machine in the oppositedirection from that electrical components, instead of the hydrauliccomponents disclosed, for controlling iiow of uid to the cylinders.

In |view of the foregoing it will be apparent to those skilled `in theart that we have accomplished at least the principal object of ourinvention and it will also be apparent to those skilled in the art thatthe embodiments herein described may be variously changed and modified,without departing from the spirit of the invention, and that theinvention is capable of uses and has advantages not herein specificallydescribed, hence it will be appreciated that the herein disclosedembodiments are illustrative only, and that our invention is not limitedthereto.

We claim:

1. A road finishing machine adapted to travel along a pair ofco-extensive tracks which lie along a roadway and are spaced graduallyvarying distances in their extent, comprising a frame includingadjustable portions extendible and retractable in a direction cross-wiseof said tracks, said portions carrying track-engaging wheels, motormeans for extending and retracting said frame portions, feeler means inengagement with said tracks and 4movable in accordance with variation intrack spacing, movement of said feeler means effecting operation of saidmotor means to adjust said frame portions to correspond to track spacingwhile said frame is in transit.

2. A road finishing machine adapted to travel along a pair ofco-extensive tracks which lie along a roadway and are spaced graduallyvarying distances in their extent, comprising a main frame adapted fordisposition cross-wise of said tracks, a pair of sub-frames carried bysaid main frame, each extending from a respective side of said mainframe and adjustably mounted thereon for extension and retractionrelative to said main frame in a direction cross-wise of said tracks,motor means for extending and retracting each of said sub-frames, amovably mounted feeler wheel in engagement with each track, each wheelhaving double flanges for engagement with opposite sides of its track,said feeler wheels moving away from each other by divergence of saidtracks and moving toward each other by convergence of said tracks, andcontrol means actuated by movement of said feeler wheels and operableto'effect operation of said motor means only when said feeler wheels aremoved toward or away from each other.

References Cited in the tile of this patent UNITED STATES PATENTS137,308 McCauley Apr. 1, 1873 179,774 Eaton July 11, 1876 298,736 Dunbaret al. May 20, 1884 664,560 Lahue Dec. 25, 1900 1,180,327 Simpson Apr.25, 1916 `1,614,029 Holdsworth Jan. 11, 1927 1,662,257 Valerio Mar. 13,1928 2,346,370 Eustis et al. Apr. 11, 1944 2,556,503 Nelson June 12,1951 2,650,525 Jones Sept. 1, 1953 2,681,231 Kondracki June 15, 19542,767,995 Stout Oct. 23, 1956 FOREIGN PATENTS 733,458 France July 11,1932 737,575 Germany July 24, 1943 511,621 Great Britain Aug. 22, 1939

